The invention generally relates to the treatment of bone conditions in humans and other animals.
The deployment of expandable structures, generically called xe2x80x9cballoons,xe2x80x9d into cancellous bone is known. For example, U.S. Pat. No. 4,969,888 and 5,108,404 disclose apparatus and methods using expandable structures in cancellous bone for the fixation of fractures or other osteoporotic and non-osteoporotic conditions of human and animal bones.
The invention provides systems and methods for treating bone.
According to one aspect of the invention, the systems and methods treat at least two vertebral bodies in a spinal column. The systems and methods make use of first and second tool assemblies operable to treat an interior region of, respectively, a first vertebral body and a second vertebral body in the spinal column. The systems and methods provide directions for operating the first and second tool assemblies to treat the first and second vertebral bodies, at least for a portion of time, concurrently.
According to another aspect of the invention, the systems and methods employ a device for compacting cancellous bone. The device comprises a wall adapted to be inserted into bone and undergo expansion in cancellous bone to compact cancellous bone. The systems and methods include a cortical bone plugging material inserted into the bone either before or after expansion of the device.
According to another aspect of the invention, the systems and methods include an instrument introducer defining an access passage into cancellous bone through cortical bone. The systems and methods also include an instrument including a distal body portion having a dimension sized for advancement through the access passage to penetrate cancellous bone. In one embodiment, the instrument includes a proximal stop having a dimension greater than the access passage and having a location to prevent penetration of the distal body portion beyond a selected depth in cancellous bone. In another embodiment, the distal body region includes a blunt terminus to tactilely indicate contact with cortical bone without breaching the cortical bone.
According to another aspect of the invention, the systems and methods use an instrument introducer defining an access passage into cancellous bone through cortical bone. A gripping device restes on an exterior skin surface and engages the instrument introducer to maintain the instrument introducer in a desired orientation.
According to another aspect of the invention, the systems and methods include a device adapted to be inserted into bone in a collapsed condition and thereafter expanded to form a cavity in cancellous bone. The systems and methods employ a fluid transport passage to convey fluid from a source into the cavity to resist formation of a vacuum inside the cavity as the device is returned to the collapsed condition and withdrawn from bone.
According to another aspect of the invention, the systems and methods include a device adapted to be inserted into bone and undergo expansion in cancellous bone. A transport passage conveys an expansion medium into the device. The expansion medium includes an amount of material to enable visualization of the expansion. The systems and methods include an exchanger assembly communicating with the transport passage and operating to reduce the amount of material present in the expansion medium within the device.
Another aspect of the invention provides systems and methods for forming an opening in cortical bone. In one embodiment, the systems and methods employ a support body including a flexible shaft portion. A cortical bone cutting element is carried on the flexible shaft portion. The element operates to form an opening in cortical body in response to application of force. In another embodiment, a cortical bone cutting element is carried on a support body to form an opening into the bone. An expandable structure also carried on the support body and adapted to be inserted through the opening and expanded to form a cavity in cancellous bone.
Features and advantages of the various aspects of the invention are set forth in the following Description and Drawings, as well as in the appended Claims.